Class: Cequel::Schema::TableReader

Inherits:
Object
  • Object
show all
Defined in:
lib/cequel/schema/table_reader.rb

Overview

A TableReader will query Cassandra’s internal representation of a table’s schema, and build a Table instance exposing an object representation of that schema

Since:

  • 1.0.0

Constant Summary collapse

COMPOSITE_TYPE_PATTERN =

Since:

  • 1.0.0

/^org\.apache\.cassandra\.db\.marshal\.CompositeType\((.+)\)$/
REVERSED_TYPE_PATTERN =

Since:

  • 1.0.0

/^org\.apache\.cassandra\.db\.marshal\.ReversedType\((.+)\)$/
COLLECTION_TYPE_PATTERN =

Since:

  • 1.0.0

/^org\.apache\.cassandra\.db\.marshal\.(List|Set|Map)Type\((.+)\)$/

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(keyspace, table_name) ⇒ TableReader

Returns a new instance of TableReader.

Parameters:

  • keyspace (Metal::Keyspace) —

    keyspace to read the table from

  • table_name (Symbol) —

    name of the table to read

Since:

  • 1.0.0



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# File 'lib/cequel/schema/table_reader.rb', line 37

def initialize(keyspace, table_name)
  @keyspace, @table_name = keyspace, table_name
  @table = Table.new(table_name.to_sym)
end

Class Method Details

.read(keyspace, table_name) ⇒ Table

Read the schema defined in the database for a given table and return a Cequel::Schema::Table instance

Parameters:

  • keyspace (Metal::Keyspace) —

    keyspace to read the table from

  • table_name (Symbol) —

    name of the table to read

Returns:

  • (Table) —

    object representation of table in the database, or ‘nil` if no table by given name exists

Since:

  • 1.0.0



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# File 'lib/cequel/schema/table_reader.rb', line 28

def self.read(keyspace, table_name)
  new(keyspace, table_name).read
end

Instance Method Details

#read ⇒ Table

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Read table schema from the database

Returns:

  • (Table) —

    object representation of table in the database, or ‘nil` if no table by given name exists

Since:

  • 1.0.0



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# File 'lib/cequel/schema/table_reader.rb', line 51

def read
  if table_data.present?
    read_partition_keys
    read_clustering_columns
    read_data_columns
    read_properties
    table
  end
end